Method of manufacturing copying papers and a copying paper



Aug. 31, 1965 sHozo MlNo ETAL 3,203,832

METHOD OF MANUFACTURING COPYING PAPERS AND A COPYING PAPER Filed May 5, 1965 2 Sheets-Sheet l l INVENTOR BY MMM AToRA/Ers Aug. 31, 1965 sHozo MlNo ETAL 3,203,832

METHOD OF MANUFACTURING COPYING PAPERS AND A COPYING PAPER Filed May 3, 1965 2 Sheets-Sheet 2 11 \9 l5 SHozo MIA/o INVENTOR.

United States Patent O '3,203,832 METHD F MANUFACTURING CPYING PAPERS AND A COPYING PAPER Shozo Mino, Ikeda, and Sumio Otani, Yao, Japan, assignors to Carbon Paper Co. Ltd., Osaka, `Iapau Filed May 3, 1963, Ser. No. 277,753 'Claims priority, application Japan, May 25, 1952, .f/21,751; Feb. 5, 1953, '3S/6,258 l IClaims. (Cl. 117-363,)

This invention relates to a copying paper and a method of making copies using the copying paper.

According to the present invention, there is provided a copying paper consisting of a number of sheets in layers and comprising a covering layer on the surface of a lower sheet of a dilerent color from the face or another layer on the surface of said lower sheet, which first-mentioned layer on said lower sheet is exfoliated and adapted to adhere to an upper sheet when subjected to pen pressure or typewriting pressure, and an adhesive layer on the under surface of the upper sheet adapted to adhere to the parts of said layer which are exfoliated only at the time of said pen pressure or typewriter pressure.

The invention also provides a method of making copies which comprises exfoliating a covering layer on the surface of a lower sheet from said surface and adhering the layer to an adhesive layer adjacent the under surface of an upper sheet by pen pressure or typewriting pressure, and exposing la coloured part of a coloured face or layer under said covering layer and consequently providing the desired impressions in said coloured part.

The present invention provides copying papers which can be handled without staining the hands and these papers can be preserved for a long time without degeneration, discolouration or disappearance of the impressions copied during handling and preservation and also provides a method for making many copies easily and clearly, and finally the invention provides a method which increases oice eiciency greatly without using normal carbon papers.

Copying papers coated with carbon ink, that is to say, physical copying papers used in conventional methods, have many faults, e.g. they stain hands and papers which touch the surface coated with carbon ink, in spite of little change in their quality and character, and also copying papers of the type which can be colour-developed by chemical change or oxidation by contacting one face with a dye and the other face coated with an oxidizing agent do not stain hands and papers and provide a good white copy, but they have the fault that they may change their quality, that is to say, they lose their copying ability and may change colour or fade.

The present invention will be described with reference to the accompanying drawings, in which:

FIG. l is a perspective view, partly in section, of a sheet of copying paper according to the invention;

FIG. 2 is a sectional view of the copying paper of FIG. l;

FIG. 3 is an exploded perspective view of several sheets of copying paper arranged in layers;

FIG. 4 is an exploded sectional view of several sheets of copying paper after pen pressure or typewriting pressure has been exerted on them;

FIG.. 5 is a perspective view, partly in section, of a modied form of a sheet of copying paper according to the invention;

FIG. 6 is a sectional view of the copying paper of FIG. 5;

3,203,832 Patented Aug. 3l, l965 rice FIG. 7 is an exploded perspective view of several sheets of copying paper ,arranged in layers; and

FIG. 8 is an exploded sectional view of several sheets of copying paper after pen pressure or typewriting pressure has been exerted on them.

Referring to FIGS. 1 to 4, a coloured paper lis provided with a coloured layerZ of a white Vcoloni' or another dilIerent colour from the color of said coloured paper 1 on its surface and an adhesive layer 3 adjacent its under surface. A copying paper 4 consists of said paper 1, coloured layer 2 and adhesive layer 3.

When using the copying paper 4 in practical cases there are a few occasions when it becomes necessary to stack up only several sheets of said paper 4. Nevertheless, there are frequent occasions when the combination of a top sheet 5 with an adhesive layer 3 under its base, several sheets of copying paper 4 piled up under said sheet 5 and a bottom sheet 6 of said paper 1 with said layer 2 on its surface under said paper 4 can be used as one set, as illustrated in FIG. 3 and FIG. 4. On such occasions, when pen pressure from a rigid pen such as a ball point pen, or typewriting pressure is applied to said set, one portion 7 of said coloured layer 2 will be separated from the layer to adhere closely to said adhesive layer 3 under the base up of the upper sheet and consequently will be exfoliated from said layer 2 to expose the surface 8 of said paper 1 under the portion of said layer 2 exfoliated at the time the sheets of said set are separated from each other. For example, if the coloured paper 1 is completely black or its one face touching coloured layer 2 is black and said layer 2 is white or yellow in colour, the surface 8 of said paper 1 with black colour will be exposed only in the area pressed to manifest black characters clearly against the white or yellow background provided by said layer 2. Said coloured paper is usually of a dark colour, such as black, blue, red, green or purple, and this colour should be selected to contrast with the colours of said coloured layer 2, such as white or yellow or light shades of red, blue or green.

The coloured paper 1 is dyed with a pigment or dye and an inorganic pigment is preferred, for example, carbon black, which is imrniscible with the flux at the time of coating said coloured layer 2, or paper 1 is coated on one face with said pigment or dye and a suitable binder.

The top sheet 5 should be a white or light-coloured paper which will show characters on its surface from al ball point pen, pencil or typewriter. The coloured layer 2 is a film on the coloured face `of said paper 1 and said iilm is characterized by the fact that during handling of the paper said lm is not exfoliated from the paper 1 to stain hands or papers and only the parts pressed by pen pressure or typewriting pressure are exfoliated from the coloured layer to adhere to the adhesive layer 3 for several sheets of copying paper 4 arranged in layers.

'Ihe coating iilrn comprises coating lm forming components, pigment, fats and fatty oils containing wax or waxlike compounds, or oily or fatty compounds. Plasticizers which are unnecessary at the time of using pliable coating tilm forming components should be coated on said coloured face as solutions or emulsions The ux or water in the coating ilm is evaporated after completing the coloured layer. The coating film forming components, pigment, oily and fatty compounds, should be immiscible with each other and at least 60% of the gross volume of the -oily and fatty compounds shouldl be xed and non-drying, and should not cause changes in said coating forming components and pigment.

Many combinations of each component suitable under various conditions are within the present invention and examples of formulations for the White-coloured layer are set out below:

Formulation l: parts Coating film forming component, nitrocellulose Plasticizer, dioctylphthalate 3 Oily and fatty compound, polyethyleneglycol 12 Pigment, titan White Flux, methanol 80 Formulation 2:

Coating film forming component, shellac 6 Plasticizer, castor oil 6 Oily and fatty compound, stearic acid 3 Pigment, zinc white Flux, methanol 80 Formulation 3:

Coating film forming component Vinyl chloride 85 Vinyl acetic 15% 15 Polymerization degree of copolymer 250 Oily and fatty compound, castor-oil 20 Pigment, titan White 50 Fluxmethylethylketone 100 toluene 150 Formulation 4:

Coating film forming component,

rubber chloride 3 Oily and fatty compound- Mineral oil 7 Calcium stearate 8 Stearic acid 3 Pigment, titan white 30 Flux- Methylethylketone 20 Toluene 60 Formulation 5:

Coating film forming component, gelatin 1.5 Oily and fatty compound, stearic acid 1.4 Dispersant, grained Soap 1 Pigment- Titan white 5 Plaster l2 Flux, water 30 Among film forming components useful in carrying out the present invention are, c g., resins having film forming ability as used in the ink industry and paint industry, among which are cellulose derivatives, synthetic resins, natural resin and its denaturation substances, rubber-like resins and protein-like resins. Pigments and dyes which are miscible in the flux or oily and fatty compounds are not useful in carrying out the present invention, since they infiltrate into the coloured paper and interfere with the clearness of characters at the time of coating the coloured layer.

Among oily and fatty compounds useful in carrying out the present invention are fats and fatty oils, e.g., castoroil, lanoline, hardened oil, and non-drying oils, eg., mineral oil, petrolatum, and Wax or Wax-like compounds miscible in fiux, e.g., carnauba wax, stearon, stearie acid, and metallic soap, e.g., fatty acid, calcium stearate, and polyhydric alcohols, e.g., glycerine, polyethylene glycol, stearyl alcohol, and higher alcohols. The oily and fatty compounds should be fixed and non-drying.

In view of the above mentioned characteristics of the coating film of said coloured layer, the pigment and oily and fatty compounds are dispersed uniformly and fixed to said coloured paper through the coating film forming components, and are immiscible with each other, so that the coating film forming molecules are fixed and do not exfoliate from said coloured paper. The components may be rolled or milled in a colloid mill or ball mill and are dissolved and dispersed uniformly into a flux and coated onto the surface of the coloured paper by roller-coating or spraying, and the flux is coated thinly and uniformly by vaporizing with drying apparatus.

The adhesive layer 3 consists of .a coating Ifilm coated on the Whole surface or -on the necessary parts of the opposite face to said coloured layer 2 of said paper 1. Said coating film :of said layer -3 provides the .adhesive action which acts to cause the exfoliated parts pressed from sai-d coloured layer 2 4of the lower coloured paper 1 to `adhere to the adhesive layer 3 of the upper coloured paper 1 only when pressure is exerted on the paper when several sheets of copying paper 4 4are arranged in layers.

Examples of the Whitecoloured layer are set out below:

Formulation 1: Parts Wax, microwax 10 Pigment, titan White 2 Formulation 2:

Wax, paraffin 8 Metallic soap, calcium stearate 1.5

Formulation 3:

Wax, paraffin 7 Synthetic resin, polyethylene 2 Pigment, titan White l Formulation 4:

Wax, paraffin 7 Natural resin, rosin 3 Formulation 5:

Cellulose derivative, nitrocellulose 3 Natural resin, rosin l Flux, methanol l0 Formulation 6:

Synthetic resin- Vinyl chloride 85% Vinyl acetic 25% l0 Polymerization degree of copolymer 200] Plasticizer, dioctylphthalate 10 Flux- Methylethylketone 20 Toluene 40 Formulation 7:

Rubber-like resin, rubber chloride l0 Plasticizer, castor-oil 7 Flux, toluene Pigment, titan white l0 Among the adhesive layers 3 most effective in carrying out the present invention are, e.g., the combination of wax and high polymer miscible with the wax and the combination of Wax and metallic soap, 'both having a melting point of over 50 C., and also useful in the yadhesive layer .are cellulose derivatives, synthetic resins, rubber derivatives, natural resin yderivatives and plasticizers.

The adhesive `layer is coated thinly and uniformly by means of roller-coating or spraying in the fused state or `as an emulsion, or solution in flux. Also, the adhesive layer may be coloured the same colour as the coloured layer 'by mixing the required pigment into it.

In view of the above mentioned characteristics of the copying paper of the present invention, it is possible to handle copying papers Without staining hands or papers and to preserve copying papers for a long time without degeneration, discolouration or disappearance of characters copied during its handling and preservation and also to provide many copies easily and clearly, and finally t-o increase ofiice eliiciency greatly Without using normal carbon papers.

Referring to FIGS. 5 to 8, a blank form 9 is provided with an adhesive layer 10 under its base, .a coloured layer 11 on its surface and white-coloured layer 12 to cover said layer 11. The adhesive layer 10 consists of -a coating on the bottom of said form 9 of a solution of one or more fats, fatty oils, waxes, natural resins, synthetic resins, rubber-like resins, or cellulose derivatives and plasticizers with ux, and also sai-d coloured layer 11 consists of a coating or printing of printers ink on the surface of said form 9.

The white-coloured layer 12 consists of a coating of resin, fats and fatty oils immiscible with each other and a white pigment on the surface of said coloured layer 11. The copying paper 13 consists of said blank form 9, said layers 10, 11 and said layer 12. When using said paper 13 in practical instances, there are a few occasions when it becomes necessary to pile up several sheets of said paper 13.

Nevertheless, referring to FIG. 7 and FIG. 8, there are frequent 'occasions when the combination of a top sheet 14 with an adhesive ylayer 10 under its base, several sheets lof copying paper 13 piled up under said sheet 14 and a bottom sheet ,15 with a coloured layer 11 on the surface of said form 9 covered 'by a whiteacoloured layer 12 under said paper 13 is used as :one set.

Also, referring to FIG. 8, when pen pressure .provide-d by a rigid pen such as an iron pen [or ball point pen, Vor typewriter pressure is applied to said set, the one portion 16 of the coloured .layer 11 to which pressure has been -applied will be separated from the other portions Vto adhere closely to the adhesive layer 10 :and will be exfoliated from the layer 11 to expose the surface 17 of said layer coated with the coloured printers ink at the time of the 'separation of the sheets `of said set from each other, so that desired impressions are manifested on the surf-ace of said paper clearly.

The adhesive layer 10 consists of .a combination of fats and fatty oils, -or Wax, or natural resin, synthetic resin, cellulose derivatives, or rubber-like resin and plasticizer. The layer 10 provides the adhesive .action which normally does not cause layer 10 to ladhere to the other sheet, yand acts to cause the parts exfoliated from the White-coloured ink-layer 12 of the lower blank form l9 to Iadhere to the .adhesive layer 10 only at the time pressure is exerted on the several sheets of copying paper `13 arranged .as 4a set in layers.

Also, the white coloured layer 12 consists of synthetic resin, white coloured pigment, and fats and fatty oils which lare immiscible with synthetic resin, and the coloured `layer '1-1 consists of a coating of printers ink.

Practical instances are illustrated next.

Firstly, on the one face of the copying paper, a solution of:

Parts Vinyl acetic 15% Vinyl chloride 85% l0 Polymerization degree of copolymer 200 Dioctylphthalate l0 Flux:

Methylethylketone Toluene Parts Vinyl acetic 15%] Vinyl chloride 85% 2() Polymerization degree of copolymer 300] Castor-oil l0 Titan white 35 Flux, methylethylketone 60 is roller-coated and after vaporizing the flux, a white colored layer of vinyl copolymer, castor-oil and titan white is formed to cover the lower colored layer. Said castor-oil is immiscible with the vinyl copolymer. Among said layers only the white-coloured layer is capable of being exfoliated by pressure. It is better to manifest impressions for said coloured layer that select the film to be immiscible with the flux of the white-coloured layer.

What is claimed is:

1. A plurality of sheets of copying paper each consisting of a base sheet member having the face thereof colored with a dark color, a layer over said dark colored face of a different color than the color of the face of said base sheet member, the different color being a light color and said layer being of a material which can be exfoliated from said colored face of said base sheet member and which will readily receive ink from conventional Writing instruments, and a layer of pressure sensitive adhesive on the back of said base sheet member and having a light color substantially the same as said light colored layer on the face of said base sheet member, said sheets of copying paper being stacked with the colored layers on one sheet of copying paper against the adhesive layer on the back of the next adjacent sheet copying paper, whereby when pressure is exerted on the stack of sheets by a pen or typewriter or the like from the direction toward which said light colored layers are facing, the material in the layers of light colored material on the base sheet members is exfoliated and adheres to the layer of adhesive on the next adjacent sheet of copying paper and exposes the darker colored face 0f the base sheet member through the space left by the exfoliated material in the shape of the pattern of pressure exerted when the sheets of copying paper are separated.

2. A plurality of sheets of copying paper as claimed in claim 1 in which said base sheet member consists of a sheet of paper having the surface thereof colored.

3. A plurality of sheets of copying paper as claimed in claim 1 in which said base sheet member consists of a sheet of paper and a layer of colored material of a light color on the face thereof.

4. A plurality of sheets of copying paper as claimed in claim 1 in which said light colored layer on said base sheet member is a coating film comprising: a lm forming component; a pigment; a member taken from the group consisting of non-volatile fats and fatty oils, oily compounds and fatty compounds; a plasticizer; and a vehicle in which the materials are placed for coatingonto said base sheet member, the coloring material for coloring the face of said base sheet member being substantially immiscible with the vehicle for said coating materials, and said iilm forming component is a resin taken from the group consisting of cellulose derivatives, synthetic resins, natural resins and their denaturation substances, rubber-like resins, and protein-like resins, and at least 60% of the gross volume of said oily and fatty compounds are non-drying, and said adhesive layers on the backs of said sheets each comprise a heat meltable mixture of wax and a member taken from the group consisting of high polymer material miscible with wax and metallic soap.

5. A plurality of sheets of copying paper as claimed in claim 1, and further comprising a top sheet consisting of a base sheet and a layer of pressure sensitive adhesive on the back of the top base sheet, and a bottom sheet consisting of a base sheet having the face thereof colored with a dark color, a layer over said dark colored face of said bottom base sheet of a different color than the color of the face of said bottom base sheet, the different color being a light color and said layer being of a material which can be exfoliated from said colored face of said base sheet.

(References on following page) References Cited bythe Examiner UNITED STATES PATENTS Foster 282-28 Brown 282-28 Easterbrooks 282-28 X West 282-28 8 2/32 Strawn 282-28 11/38 Sherman et al. 282-28 EUGENE R. CAPOZIO, Primary Examiner.

LAWRENCE CHARLES, JEROME SCHNALL, LEON- ARD W. VARNER, Examiners. 

1. A PLURALITY OF SHEETS OF COPYING PAPER EACH CONSISTING OF A BASE SHEET MEMBER HAVING THE FACE THEREOF COORED WITH A DARK COLOR, A LAYER OVER SAID DARK COLORED FACE OF A DIFFERENT COLOR THAN THE COLOR OF THE FACE OF SAID BASE SHEET MEMBER, THE DIFFERENT COLOR BEING A LIGHT COLOR AND SAID LAYER BEING OF A MATERIAL WHICH CAN BE EXFOLIATED FROM SAID COLORED FACE OF SAID BASE SHEET MEMBER AND WHICH WILL READILY RECEIVE INK FROM CONVENTIONAL WRITING INSTRUMENTS, AND A LAYER OF PRESSURE SENSITIVE ADHESIVE ON THE BACK OF SAID BASE SHEET MEMBER AND HAVINGA LIGHT COLOR SUBSTANTIALLY THE SAME AS SAID LIGHT COLORED LAYER ON THE FACE OF SAID BASE SHEET MEMBER, SAID SHEETS OF COPYING PAPER BEING STACKED WITH THE COLORED LAYERS ON ONE SHEET OF COPYING PAPER AGAINST THE ADHESIVE LAYER ON THE BACK OF THE NEXT ADJACENT SHEET COPYING PAPER, WHEREBY WHEN PRESSURE IS EXERTED ON THE STACK OF SHEETS BY A PEN OR TYPEWRITER OR THE LIKE FROM THE DIRECTION TOWARD WHICH SAID LIGHT COLORED LAYERS ARE FACING, THE MATERIAL IN THE LAYERS OF LIGHT COLORED MATERIAL ON THE BASE SHEET MEMBERS IS EXFOLIATED AND ADHERES TO THE LAYER OF ADHESIVE ON THE NEXT ADJACENT SHEET OF COPYING PAPER AND EXPOSES THE DARKER COLORED FACE OF THE BASE SHEET MEMBER THROUGH THE SPACE LEFT BY THE EXFOLIATED MATERIAL IN THE SHAPE OF THE PATTERN OF PRESSURE EXERTED WHEN THE SHEETS OF COPYING PAPER ARE SEPARATED. 